JPS58199170A - System for correcting positive and negative printing shift - Google Patents

Abstract

PURPOSE:To obtain a printing result with good quality, by a method wherein the moving speed of a carrier is measured and a time flowing a current through a printing head after a dot pulse is generated is controlled to eliminate the printing shift of the dot when a motor speed is varied. CONSTITUTION:The titled system is equipped with a carrier 2 reciprocally moved in a state holing plural printing heads H in a row toward a lateral direction, a plate 5 integrally connected to the carrier 2 and having plural printing position detecting slits arranged in parallel at intervals equal to the slit width, a sensor for detecting the slit positions and a delay circuit 12 delaying the dot pulse signal of the sensor 13 showing the front and the rear flange of each slit to send the same to a control apparatus. In addition, a speed detecting slit is provided to the plate 5 and the time difference of the pulse generated at the front flange of the speed detecting slit and the pulse generated at the rear flange thereof is calculated by monitoring the output of the sensor 13 by the control apparatus 10 while a means adjusting the delay amount on the basis of said time difference is provided and printing data is sent to each head H to carry out printing operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a forward/reverse printing misalignment correction method for correcting forward/reverse dot misalignment in a shuttle printer that prints dots by moving the print head back and forth.

[Prior art and problems]

FIG. 1 is a diagram showing an outline of the shuttle printer, FIG. 2 is a diagram showing the printing position during normal printing, and FIG. 3 is a diagram showing the printing position according to the conventional printing method when the speed is increased. In the figure, 1 is print paper, 2 is carrier,
3 is a printing pin, 4 is a solenoid, 5 is a slit plate for detecting printing position, 6 is a slit detector, 7 is a slit for detecting printing position, H is a printing made by printing pin 3 and solenoid 4.
・Shows the throat.

The shuttle printer has a carrier 2 equipped with a plurality of printing hands H arranged in a row in the lateral direction, as shown in Figure 1. Assume that, for example, a character string of one button digit is to be printed on the printing paper 1, and that the carrier 2 is provided with an additional number of printing hesids H.

It is sufficient to print four-digit characters on each print head H.

In this case, when carrier 2 moves from left to right to print a 4-digit character, 1 dot line of 1 line of character string can be printed, and then the print paper 1 is moved upward by 1 dot. When the carrier 2 moves from right to left, the next one dot line can be printed, and when it moves back and forth several times, a character string of one button digit can be printed. Slit plate 5 for detecting print position and slit 7) The detector 6 is used to detect the print position of a dot, and the slit plate 5 for detecting print position is provided with slits 7 corresponding to the print positions. Although not shown, the slit detector 6 has a light emitting element and a light receiving element. For example, when the slit comes to the position of the light emitting element, the light receiving element outputs a high level signal.

When the light emitting element and the light receiving element are interrupted, the light receiving element outputs a low level signal. The output value V of the light receiving element is waveform-shaped, and the waveform-shaped signal is differentiated by a differentiating circuit.
The second part shows the relationship between dot and pulse.
Illustrated. When the carrier 2 moves back and forth, the slit 7 crosses between the light-emitting element and the light-receiving element of the slit detector 60, and the leading and trailing edges of the slit 7 generate a ton of light as shown in FIGS. 2 (1) and (6). generates a pulse DP. When this dot pulse DP occurs, an interrupt is sent to the microprocessor. The microprocessor checks the cause of the interrupt, and if the cause of the interrupt is due to the generation of dots/< pulses, it supplies print data to the print head to perform the printing operation. In this case, the microprocessor The total time of the delay time T2 until the interrupt iRQ is notified to the microprocessor and the time T1 from the reception of the microinterrupt (RQ to printing) is set v4!I so that it matches the time interval of the dot pulse DP. Of course, the total time of TI and T
It may be an integral multiple of the pulse time interval. Therefore, when the carrier 2 moves from left to right and firstly from right to left, the dot printing positions it match as shown in FIG. 2 (3) and (4).

Conventionally, brushless motors have been optimal as carrier drive motors for shuttle printers.

AC motors are often used due to cost considerations. However, when using an AC motor, the fluctuation of the mantissa per revolution,
The influence of fluctuations in the power supply voltage and the size of the load on the rotation speed can be ignored, and as a result, the influence appears in the form of variations in printed dots.

An illustration of the misalignment of printed dots as the speed increases is shown in FIG. The time from generation of pulse DP to printing is 1 hour Tl+T!, as explained earlier in FIG. 2. Later. Here, the time T1 is the total of the microprogram processing time and the head operation time, which is 69, and the time TI is determined by a fixed delay time using a timer or one-shot multi, so during these times, the speed of the carrier drive motor is It remains constant even if the moving speed of the carrier 2 changes. Therefore, when the speed of the carrier drive motor increases and the carrier 2 moves faster than in Figure 2, the printing position when the carrier 2 moves from left to right will move to the right as shown in Figure 3 (3). Hezure, career 2
When the number moves from right to left, the printing position shifts to the left as shown in FIG. 3 (4), and a printing misalignment occurs between the first and second numbers as shown in FIG. 3.

Further, when the speed of the carrier drive motor decreases, needless to explain, the printing position shifts in the opposite direction to that described above, and printing misalignment similarly occurs.

As described above, a major drawback of the conventional shuttle printer is that printing misalignment occurs when the speed of the carrier drive motor fluctuates.

[Purpose of the invention]

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and aims to eliminate misprinting of dots even when the speed of the carrier drive motor fluctuates in a shuttle printer, and to avoid obtaining negative printing results. DERORU0 [Structure of the Invention] To that end, the forward/reverse printing misalignment compensation method of the present invention is a friend of the present invention.

It has a control device, a carrier that is provided with a plurality of print heads in a line in the horizontal direction and moves back and forth, and a plurality of print position detection slits that are integrally connected to the carrier and arranged in parallel at intervals equal to the slit width. A slit plate for position detection, a sensor for detecting the position of the print position detection slit of the position detection slit plate, and a dot-pulse signal of the sensor that indicates the position of the front edge or the rear edge of the print position detection slit. a delay circuit that delays the dot pulse and sends the delayed dot pulse to the control device;
In the shuttle printer device configured to perform processing for receiving a dot pulse from the delay circuit and performing a printing operation by supplying print data to the print head at 7t, the position detection slit plate When a speed detection slit is provided at the speed detection slit, the control device is required to monitor the output of the sensor, and the time difference between the pulse generated at the leading edge and the pulse generated at the trailing edge of the speed detection slit is determined. The present invention is characterized in that a delay amount adjusting means is provided for determining the time difference and adjusting the delay amount of the delay circuit based on the time difference.

[Embodiments of the invention]

The present invention will be explained below with reference to the drawings.0 Figure 4 is a block diagram showing one embodiment of the present invention, GS diagram is a diagram showing an outline of a slit plate for printing position detection used in the present invention, and Figure 6 is a block diagram showing an embodiment of the present invention. The figure is a diagram showing printing positions according to the present invention. In the figure, 8 is ROM (read only memory), 9 is RA
M (random access memory), 10 is MPU
(Microprocessor), 11 is I10 port, 1
2 is a delay circuit, 13 is a sensor, 14 is a printer mechanism section,
15 indicates a speed detection slit.

In FIG. 1s4, the sensor 13 is composed of a slit plate 5 for detecting print position and a slit detector 6. The output of sensor 13 is supplied to I10 port 11 and delay circuit 12. Zero delay circuit 12 delays the pulse sent from sensor 13 and applies it to the interrupt terminal of MPU 10. It was. The delay amount of the delay circuit 12 is MPU1
0 [can be changed. therefore.

It is possible to freely set the delay time Tm0
An example of such a continuous firing circuit is 1, for example, Fujitsu's MB88.
73 and Motorola's MC6840 in the US.
The printer mechanism 14, which can use a programmable timer, is composed of a carrier drive motor, a print head H, and the like. M P U 10 is I
The printer mechanism section 14 is controlled via the 10 boats 11. The MPU 10 includes the above-mentioned delay circuit 12 and I10.
11 is connected, and ROM8 and RAM9 are connected. The ROM 8 stores control programs, and the RAM 9 stores print data and character patterns (CG).The zero delay circuit 12, which has a work area, may have a programmable circuit, for example. 10 boat 11 sends printing position information etc. from sensor 13 to MPU 10,
It is used for sending carrier drive motor control commands and print head H control commands from 10 to the printer mechanism section 14. The MPU 10 measures the moving speed of the carrier 2 before starting printing, and sets the delay amount of the delay circuit 12 based on the measured value. When the micro interrupt (RQ) is sent from the delay circuit 12 to the MPU10 after a delay time T2 from the dot pulse DP, the MPU 10 senses the cause of the interrupt, and if the + interrupt cause is due to the dot pulse. The ninth process of dot printing is performed.As mentioned earlier, when printing 12 x 12 dots of characters per line using additional print heads H, #'i, 1 dot line. rC!! 12X4=48 dots are printed on each print head H, and when the carrier 2 moves back and forth six times, the printing of the character of one button digit is completed.The configuration is such that the moving speed of the carrier 2 can be detected. Fig. 5 shows an example of 50 printed position detection slit plates.The print position detection slit plate 5 is newly provided with speed detection slits 7) 15 on both sides. Incidentally, the speed detection slit 15 may be provided on one side of the frame. By providing this speed detection slit 7) 15, the time for the carrier 2 to move by the width of the speed detection slit 15 before starting printing from the left end or right end is counted, and this count value Ng is set in advance. The ratio with the standard value N8 is calculated, and the time from the dot pulse DP to the notification of 4RQ including all four sides of the microphone is controlled using this ratio. That is, the delay time T is determined in the following manner based on the time T8 of the dot-to-pulse interval at a constant speed with no speed change and the above-mentioned value.

Grain time (Ta) = Dot pulse interval time without speed change (Ta)
T1) In the above 2, 1 hour T#, Tl and Nx are determined at the time of design, and Nz is the speed detection slit 15.
I am asked for it. As can be seen from the above equation, as the moving speed of the carrier 2 increases, the measured count value N2 decreases and the gray time T2 becomes shorter, so the printing position in FIG. The printing position in Figure (4) is corrected to the right, eliminating any misprinting. Furthermore, when the moving speed of the carrier 2 decreases, the measured count value N increases and the delay time Ts becomes longer, contrary to the above, so the printing position is corrected in the opposite direction to the above, and there is no printing misalignment. Ru. If the method based on nine calculations using the above formula becomes complicated, the following method can also provide printing quality at a level that does not pose any practical problem. That is, the measured count value N,
By creating a table of delay times corresponding to the extent (range) of the difference between and the standard count value N, and indexing this table, results can be easily obtained in a short time.

The present invention detects the actual speed of the carrier 2 to determine the optimum delay time Tx, and calculates the optimum delay time T! The delay amount is set in the delay circuit 12 to correspond to the above. Then, when the dot pulse DP is sent from the sensor 13, the delay circuit 12 issues a micro interrupt 4RQ to the MPU 10 after a delay time Tm set according to the moving speed of the carrier 2. When micro interrupt 4RQ is notified from 0 delay times [12 to MPU 10, the print paper I
K dots are printed, and the printed position does not change even if the moving speed of the carrier 2 changes, as shown in Figure JI6.

Further, the actual speed of the carrier 2 measured using the speed detection slit 15 can be used for detecting abnormal speed of the carrier 2.

FIG. 7 is a flow chart showing the flow of processing of the microprocessor used in the present invention), FIG. 88 is a flow chart showing the flow of RQ (interrupt) processing of i microprocessor 7 used in the present invention 8A, 9th wA is a diagram showing an example of print output when the character dot configuration is 9×7.

The flow of processing will be explained with reference to 87m.

■ Check whether there is a command. If ONO, perform other processing; if Yes, perform the process (■).

■ Check whether it is a print command ◎ If it is N, process other commands, and if it is YO, process ■.

■ Edit one line of print data and perform the process described in ■.

■ Print one line - Edit one doctor line of the data and perform the process (■).

■　Turn on the carrier drive motor and perform the process in ■.

Go to - ■ Detect the right or left end of the slit plate and perform process (■).

■ Check whether black → white (edge of slit).

In the case of N#, repeat the check until Yll is reached, and then check Y-
In the case of 1, process (■) is performed.

■ Preset the counter.

■ Check whether white → black (edge of slit) O If no, repeat the check until s Ysa, then Y
If it is -1, it is processed as 0.

[Stocks] Read the counter value (Nx) and perform the process (■).

■ Delay time (delay time) Calculate Tm and perform 0 processing.

〇 Sect the delay time T3 to the timer. Initialize with dot counter. Dot-RQ enable state Perform 00 processing in the 0th order O ■ End 7-) Check whether the button is on.

In the case of Nt, repeat the check until -YgsK becomes 1Yaa.
If O, process 0.

0. Feed the paper by 1 dot/line and process [phase] 〇 [phase] Check whether printing for one line is completed.

If it is Nt, return to the process of KFi■') If it is % Yaa, perform the process of [phase] 0 [Phase] Turn off the carrier drive motor and perform the print operation end report.

Next, explain the flow of 4RQ (interrupt) processing with reference to the K11 Output the print data corresponding to the 0 0 dot counter,
Perform the process of Q9 O ■ Update the dot counter by +1 and perform the process of [phase].

Qo Check whether the 1-dot line has ended. For example, as shown in Figure @9, when the character dot configuration is 9 x 7 (vertical x horizontal), and if the head is used to print 4 characters as mentioned above, 1 dot, 2 I, etc. The number of dots is 12 (dots) x 4 (characters). Therefore, in this case, the value of the dot counter is updated, and when it becomes a hammer, it is determined that printing of 1 dot and 2 ins has been completed.

If it is N, perform the @ process h If Yaa, perform the [phase] process 0 @ Reset the delay time Tλ to the timer 0 @ Turn on the end flag O The process in Figure 8 is W47 0 included in the geography of Figure 00 [Effect of the invention] As is clear from the above explanation, according to misfire #4,
A speed detection slit is used to measure the moving speed of the carrier before the next carrier starts printing from the left or right end of the print head. Since the time is controlled, even if the carrier drive motor speed fluctuates due to voltage fluctuations, power frequency fluctuations, load increases, etc., forward and reverse dots and
It is possible to obtain high-quality printing results with misalignment corrected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an outline of a shuttle printer. Figure #I2 is a diagram showing the printing position during normal printing.
The figure shows the print position according to the conventional printing method when the speed increases, FIG. 4 is a pull diagram showing an embodiment of the present invention, and FIG. 6 is a diagram showing the printing position according to the present invention, FIG. 7 is a flow chart showing the processing flow of the microprocessor used in the present invention, and FIG. 8 is a diagram showing the process flow of the microprocessor used in the present invention. FIG. 9 is a flow chart showing the flow of RQ (interrupt) processing, and is a diagram showing an example of print output when the character dot configuration is 9×7. 1...Print/Paper, 2...Carrier%3...
Printing pin, 4... Lenoid, 5... Slit plate for printing position detection, 6... Slit detector, 7... Slit for printing position detection, 8... ROM (read O only memory), 9...RAM (random access memory), lO...MPU (microprocessor), 11...10 baud), 12...delay time M
, 13...sensor, 14...printer mechanism section, 1
5...Slit for speed detection, H...Print head 0 Patent consultant: Utsutsuk Electronics Industry Co., Ltd. Representative Patent Attorney Kyotani 4th Department (1 other person) 8 Figure xq l ¥l

Claims (1)

[Claims] A control device, a carrier which is provided with a plurality of printing nozzles in a lateral direction tC-row and moves back and forth, and a plurality of bright prints integrally connected to the carrier and arranged in parallel at intervals equal to the slit width. A position detection slit plate having a detection slit at the printing position, a sensor for detecting the position of the printing position wrinkle detection slit of the position detection slit plate, and the position of the front edge or the rear edge of the printing position detection slit. a delay circuit for delaying the dot pulse signal of the sensor indicating a delay amount and sending a delayed don't pulse to the control device, and the control device, when receiving the dot pulse from the delay circuit, sends the dot pulse signal to the print head. In a shuttle printer device configured to supply print data and perform processing for performing a printing operation, a speed detection slit is provided in the position detection slit plate, and the output of the sensor is provided in the control device. Delay amount adjusting means for determining the time difference between the pulse generated at the leading edge and the pulse generated at the trailing edge of the speed detection slit by monitoring the slit, and adjusting the delay amount of the delay circuit based on the time difference. A forward/reverse printing misalignment correction method that is unique in its design.